In a mobile communication system, in order to provide specific subscriber groups with better services, it is often necessary to form multiple radio resource management entities (the radio resource management entity is a network entity for managing radio resources and responsible for subscriber equipment access in a radio access network, e.g. base stations of various mobile communication systems) to a closed subscriber group (CSG) for a specific subscriber group. For example, all subscribers within a company or school is a specific subscriber group, and multiple radio resource management entities are formed to a closed subscriber group for the subscriber group to provide a special access service.
The condition is ubiquitous in mobile communication systems that multiple radio resource management entities are formed to a closed subscriber group for a specific user group. To describe the condition more clearly, the description is hereinafter given by taking a long term evolution (LTE) system of system architecture evolution (SAE) for example.
FIG. 1 is a structure diagram illustrating a LTE system. Referring to FIG. 1, in a radio access network of LTE system, radio resource management entities include a macro base station (eNB) and a home base station (HeNB), and alternatively include a HeNB gateway (HeNB GW). The eNB may be connected directly to a mobile management entity (MME) (the mobile management entity is a network entity responsible for setting up radio access bearers in the core network) in the core network; when radio resource management entities include a HeNB GW, the HeNB is connected to an MME by means of the HeNB GW; when radio resource management entities do not include a HeNB GW, the HeNB may be connected to an MME directly.
To provide more abundant services, radio resource management entities in a LTE system provide, taking a HeNB as an example, multiple types of HeNBs including opened type, hybrid type and closed subscriber group type. The opened HeNB has no specific access subscriber group and any User Equipment may be accessed to an opened HeNB. The closed subscriber group HeNB is the foregoing HeNB within a closed subscriber group and it only allows the User Equipments (to simplify the description, the User Equipment within a specific subscriber group is hereinafter referred to as CSG User Equipment), within a specific subscriber group served by the HeNB, to access the network. The hybrid HeNB forms a closed subscriber group in connection with other HeNBs, and allows a CSG User Equipment served by itself to access the network so as to provide the CSG User Equipment with higher quality access services while it may also allow other non-CSG User Equipments (the User Equipments without belonging to the CSG) to access the network.
It can be seen from the above description that, in the existing mobile communication system, not only a radio resource management entity of closed subscriber group is provided by forming multiple radio resource management entities to a closed subscriber group, e.g. a closed subscriber group HeNB, but also a hybrid radio resource management entity, e.g. a hybrid HeNB, may also be provided to provide more abundant services.